64 Journal of Comparative Neurology. 



tral surface is bent caudo-laterad, at quite an acute angle, merg- 

 ing into the fasciola on either side. At this point there is usu- 

 ally a distinct tubercle, Tiiboxuhun fasciae dentatae (Zucker- 

 kandl). In man and apes there are apparently numerous, small 

 transverse fissures, given off from the hippocampal fissure, 

 toward the fimbria, forming the so-called fascia dcntata. 

 Zuckerkandl^ divides the hippocampal portion of the arcuate 

 gyre into an inner and outer " Randbogen," the former com- 

 prising the fimbria and fornix and the latter the fasciola plus the 

 striae Lancisii. He also employs the term gynis margincilis , or 

 " Randwindung," as a synonym for indusium. 



During the fifth month of fetal life' there is recogniz- 

 able in the shallow arcuate fissure a small longitudinal bundle of 

 fibers {riervi Lancisii^ passing along the length of the cal- 

 losum. As there is considerable variation in the appearance of 

 these striae, some difference of opinion exists as to what be- 

 comes of the cephalic and caudal ends of them. It is generally 

 conceded that the caudal end passes over into the fasciola, form- 

 ing, according to Mihalkovics, the substantia reticularis alba. 

 The cephalic ead, according to Blumenau, has two terminations: 

 first, the deeper layer passing over the genu, into that portion of 

 the first (super) frontal gyre, appearing on the mesal surface, and 

 connecting with the gyrus cinguli (callosal gyre). Through the 

 intervention of this (frontal) gyre and therefore, indirectly, the 

 fibers are brought into connection with the olfactory lobe: 

 second, there is a direct connection of the superficial fibers from 

 the genu, around the edge of the frontal gyre, into the inner or 

 mesal olfactory root, giving the characteristic, whitish appearance 

 to the same. An old but undoubtedly erroneous belief is thatthe 

 callosal gyre has become elevated from the dorsal surface of the 

 callosum and has left behind a small portion of the fibers, from 

 the longitudinal association bundles. 



Spitzka^" states that the cerebral cortex covers the walls of 

 the septum lucidu)n (hemiseptums). Similarly Blumenau" says: 

 " Und in der That findet sich eine diinne graue Schicht auf der 

 betreffenden Flache, erstens an der Stelle, wo der Balken den 

 sogen. Ventriculus septi begrenzt. Diese Schicht ist derjenigen 



